mil.navy.nps.rra
Class SSP

Sound Speed Profile (SSP) describes the acoustic characteristics of refraction for
the local volume of water which the Ray is passing through.

The speed of sound in water is dependendent on water temperature, depth and
salinity. Changes in SSP cause refraction (bending) of sound waves, which
can be considered a continuous case of Snell's Law. In practice, an SSP can
be obtained from Conductivity-Temperature-Density (CTD) measurements, Expendable
Bathythermographic Thermistor (XBT) measurements or historical datasets. Because
SSP can return values of arbitrary resolution in depth and position, and since SSP
is a principal influence on sound path refraction (bending), this computaional
approach makes the rra algorithm of general use under a wide range of
underwater conditions.